1. Field of the Invention
The present invention relates to an apparatus for elevating a position determination pin and a spindle assembly for a disc player and more particularly, to an elevating apparatus for moving up and down the position determination pin and the spindle assembly in a disc player for playing alternatively a naked disc and a cartridge encased-disc by means of a pickup device and the spindle assembly.
2. Description of the Prior Arts
Nowadays, each of widely used minidisc player and compact disc player is used for reproduction of only one type of disc. Thus, if a user wants to obtain information from a different type of disc, it is necessary to separately buy a new player applicable thereto.
In general, the disc which is at a naked state or at an encased state in a cartridge is mounted on the tray to be loaded on the player. Such disc loading method depends on a structure of a disc player, so that a user can not load the discs by his own selection. Also, in fields of a common disc player used for reproducing discs of different sizes, although products which can reproduce the discs of different sizes such laser discs (LD), compact discs ,etc., can be manufactured, those can be applicable only to the discs of different sizes which are at the naked state.
Katsuichi Sakurai et al. proposes the disc player, capable of reproducing the discs, which is both at the naked state and at the encased state in the cartridge in E.P. Publication 525201 A2 (corres. U.S. Pat. No. 5,299,185).
Also, Hideo Kawachi et al. proposes the disc player capable of reproducing the discs, which is both at the naked state and at the encased state in the cartridge in E.P. Publication 518259 A3 (corres. U.S. Pat. No. 5,301,176).
Recently, the compact disc player which can selectively reproduce the compact disc and a minidisc by using a single optical pickup device and a single spindle assembly provided with a turntable, a spindle motor and a spindle shaft has been developed in order to improve disadvantages of the prior art minidisc player and compact disc player.
In the compact disc and minidisc player provided with the single spindle assembly and pickup device, since there is a predetermined height difference of compact disc tray and minidisc tray, double constructions therefor are needed in that player in order that the minidisc or the compact disc can be selectively mounted over the turntable constituting the spindle assembly. Also, the minidisc is mounted on a upper portion of the turntable constituting the spindle assembly and the compact disc is mounted on a lower portion of the turntable constituting the spindle assembly. Further, in the construction of this double turntable with difference of heights, since the discs which are mounted on respective mounting surfaces and the pickup device should always maintain a predetermined gap in reproducing the disc, the height of spindle assembly should be adjusted to the lower surface of the mounted disc.
In Hideo's patent is also disclosed an apparatus for elevating the spindle assembly wherein one side of a chassis supporting the spindle assembly of that apparatus is secured to a main chassis of the disc player and the spindle assembly can be moved up and down in a radial direction centering around the fixing point. Despite that, the apparatus for elevating the spindle assembly can be applicable to the naked and cartridge-encased discs of only the same size, so that a transfiguration of the player for driving the minidisc and compact disc of different sizes is demanded as necessary. Further, since only the one end of spindle assembly elevating apparatus is moved reciprocatingly with fixation of its other end, it is difficult to precisely adjust a position of the spindle assembly. Position determination pins to be inserted into four position determination grooves formed on a bottom surface of the cartridge encased-disc should be projected from the base plate in order to reproduce the cartridge encased disc. However, since the position determination pins put obstacles in the way of the mounting of the naked disc on the turntable, it is necessary to move those pins downward.